When pinning your sewing patterns in preparation for cutting, it is important to consider not only the type of pins you are using but also type of fabric and how many layers you are pinning through. Fabric bulk and thickness will have an affect on how well you can pin the paper pattern to the fabric layer(s) underneath as well as how flat and accurately secured you can keep the layers in the cutting process.
When working with thick, bulky or highly textured fabrics, there are two basic conventions you should keep in mind:
1. Position the pins farther apart. The beauty of thicker fabrics is that they naturally feature lots of structure and stability. For that reason, you don't need a lot of pins to prevent the paper pattern and fabric layers underneath from shifting in the cutting process. As a matter of fact, when it comes to thick/bulky fabric, the less pins you use, the flatter the fabric layers will remain underneath.
Using less pins and positioning them less densely and only at key points (such as corners and edge mid-points) will prevent rippling and tension in the fabric layer(s). Naturally, the garment's final fabric pieces will result in a smoother, more accurate cut along all edges.
2. While pin placement is important in keeping the pattern and fabric layers flat and smooth along all edges, the type of pins you use is equally important in achieving a fully secured pattern.
Although you'll find a few different options on the market, choose pins that are longer, sharper and thicker, featuring either a T-shaped or sphere end (shown above). Having some sort of extension will aid in comfortably inserting and removing the pins through the paper and thick fabric layers underneath. As you become a more advanced dressmaker, you will find that both pin length and sharpness are essential in achieving a fully stabilized pattern when working with unique, heavyweight fabrics.
Note: Sometimes, the fabric is too thick and bulky and thus pins alone are not sufficient to keep the pattern flat and smooth in the cutting process. In this case, you can use fabric weights alone to stabilize the pattern. If relying solely on fabric weights, cutting the pattern should be done very carefully, following its outer edges as accurately as possible.